Messages

3221

General Mach Discussion / Re: Help with motor tuning xyz profile settings mach3

« on: January 20, 2019, 03:56:04 AM »

Hi,
those Delta servos are really good and a ton of power.

If you don't mind me asking why you spent all that money on really good servos and then buy an XHC controller?

Craig

3222

General Mach Discussion / Re: Help with motor tuning xyz profile settings mach3

« on: January 20, 2019, 03:26:23 AM »

Hi,
the typical maximum pulse input rate to a step/direction servo drive is 500kHz and that assumes differential signaling.
If you wish to maximize both resolution and speed you need to signal the servo drive with differential line
drivers. Commonly it is an added complication that is over the top and not required. We shall see once we do the
calculations.

I assume the servos are rated to 3000 rpm? If they are hooked directly to 10mm pitch screws then at 3000 rpm the axis would
be moving at 30 m/min.....quite respectable for a production machine and WAY quick for a hobby machine.

Lets assume that rather than signaling at 500kHz we chose a much easier  signaling rate, say 100kHz. This could be done
without line drivers but just simple open collector outputs.

At a step rate of 100kHz that equates to:
pulses per minute = 100,000 X 60
                           =6,000,000
the pulses per rev =6,000,000 /3,000
                           =2000 pulse per revolution.
Linear resolution = 10 (mm pitch) / 2000
                         = 5um   (or 0.0002 inch per step)

Thus if you made choices such that the maximium step pulse rate is 100kHz that would still allow you to spin the servo
at its maximum speed with a steps per revolution of 2000 and with your 10mm pitch screw that works out to 5um
resolution....pretty damned good. You could do better if you wish by either decreasing the maximum speed or attempt to
signal the servo drive faster.

If that sounds good to you I suggest you program the drive to accept 2000 input pulses to cause the servo to complete one revolution.

I presume you have set the servo drive up in Position Mode (Step/Direction)? You can use the Low speed input, it will make it that
much easier. That is parameter P1-00 on page 6-3

You need to confirm that parameter P1-46 is set at its default of 2500. That means the encoder is effectively 2500 lines
and because of quadrature encoding that means 10,000 count per rev.

Now we know what electronic gearing we require, the encoder is 10,000 count per rev whereas we want 2000 input pluses
to cause the servo to revolve once. Thus the ratio is 5:1.

So the Numerator N1 parameter P1-44 page 6-8 should be set to 5000 say and therefore the Denominator M parameter
P1-45 on age 6-8 should be set to 1000.

Now you can set Machs motor tuning parameters. We have set the servo drive up to revolve once with 2000 pulses and the
axis will move 10mm . Thus the steps per unit are 2000 /10 =200. I'm assuming you native units are millimeters.
Your max velocity will be 30,000 mm/min and you could probably set those great big kick-arse servos up for an acceleration of
1000 mm/sec/sec to start with. The servos themselves I'm guessing wont be working at all at that piddling rate. I suspect
unless you have a really big or heavy machine you could take the accel up to 10,000 mm/sec/sec. Your machine is going
to Rock-and-Roll!!!!

Craig

3223

Mach4 General Discussion / Re: Poor Mans Wizard

« on: January 20, 2019, 01:31:59 AM »

Hi Chad,
have started digging into the wxWidgets morass.....and surprise surprise I'm making some progress.

There are broadly speaking 19 different dialogs. The one in the code I have posted is an example of a FileDialog.
Other dialogs that may be useful to you and I are TextEntryDialog, NumberEntryDialog and MessageDialog.

I could never understand why it is for instance that it was necessary to have a Frame, called mainframe in my example,
and a panel within that frame, called panel in my example, but was not in fact used?

What I have learnt is that a dialog, essentially a bunch of code to do some nifty things, requires a parent structure because a fair
proportion of the code that does all that nifty stuff is inherited from the parent.

There again in the example posted 'mainframe' is the top level, note that its first parameter, usually its parent is wx.NULL,
ie no parent. Note that 'panel' which lives inside the frame has its first parameter as 'mainframe', so 'panel' parent
is 'mainframe' and 'panel' inherits code from 'mainframe'.

When I have defined 'file' as a FileDialog its first parameter or parent is 'panel'. So FileDialog 'file' inherits from both
'panel' its immediate parent but also from 'mainframe' as well.

It is possible to have a FileDialog WITHOUT a parent but then it misses out on all that code. For instance we know that
most windows can be resized by dragging the boundaries. That functionality is associated with Frame. Thus if we had
a FileDialog that does NOT inherit from a Frame then that resize functionality would be lost.

The next thing I have learnt is that while the FileDialog in my code is:

Code: [Select]

local file = wx.wxFileDialog(panel, "Select Data File", "", "", "Text files (*.txt)|*.txt|Tap files (*.tap)|*.tap",
                             wx.wxFD_SAVE,wx.wxDefaultPosition,wx.wxDefaultSize, "File Dialog" );
It does not DO ANYTHING YET. That is the purpose of the constructor.....in my example the constructor is:

Code: [Select]

file:ShowModal()
Its that statement that causes the defined file dialog to be displayed on screen.
If a Dialog has a constructor it also needs a destructor and in many cases when we hit <OK> or <Save> or <Yes>
in a Dialog window that triggers the destruction of the dialog.

Yes after spending a couple of hours reading and writing snippets of code to test what I've read its starting to make a
little sense!

Craig

3224

General Mach Discussion / Re: Help with motor tuning xyz profile settings mach3

« on: January 20, 2019, 12:48:38 AM »

Hi,
what controller or are you using a parallel port? We need to know the maximum pulse rate your motion control
(be it external OR parallel port) solution can produce.

What pitch is the ballscrew?
Is there a gear or belt reduction between the servo and the ballscrew?

Craig

3225

General Mach Discussion / Re: ethernet or usb which is better

« on: January 19, 2019, 10:42:37 PM »

Hi,
Ethernet is the preferred option.

Ethernet communication is very fast which reduces latency. Ethernet signals are transformer isolated at each end
and avoid power supply clashes and are generally much more resistant to electrical interference. Ethernet cables
can be long, tens or even 100 meters whereas USB cables beyond a meter in length become increasing susceptible
to noise or communication failure.

It is only fair to point out that you can get transformer isolated USB cables as well but at a price and they are not the norm.

Craig

3226

Mach4 General Discussion / Re: TouchOff Module Error... need help

« on: January 19, 2019, 04:32:08 PM »

Hi,
I am using 3804 and without that difficulty.

Do you wish to raise a Support Ticket with NFS or do you want to try to understand and fix it yourself?

The diagnostic error message narrows down where you have to look.

Open the Zero Brane Editor and navigate to the Mach4Hobby\Modules\mcTouchOff.lua.

This is the code that occurs at line 911 through 915:

Code: [Select]

UI.frameMain:Connect( wx.wxEVT_UPDATE_UI, function(event)
frameMainOnUpdateUI()

event:Skip()
end )
So exactly as the diagnostic suggests the error occurs in the function frameMainOnUpdateUI().
That function is defined in lines 1158 through 1188 and I have copied it here:

Code: [Select]

function frameMainOnUpdateUI()

mcState, rc = mc.mcCntlGetState(inst)
if (co ~= nil) and (mcState == 0) then
local state = coroutine.status(co)
if state == "suspended" then --We are about to run some more code so check to see if we have to check the probe state
local IsOk = true;
if ( m_CheckProbe == true) then --The probe should be active at the end of the move
IsOk = CheckProbe(1)
else
IsOk = CheckProbe(0) --The probe should NOT be active at the end of the move
end
if ( IsOk == false ) then --If the check failed lets kill the Coroutine
co = nil
IsOk = true
else
coerrorcheck, rc, m_CheckProbe = coroutine.resume(co)
if(coerrorcheck == false) then --Something happened here to the coroutine so kill it
co = nil
end
if(rc < 0) then --Something happened in the Gcode and we have an error So Kill the coroutine
co = nil
end
end
end

if state == "dead" then --Kill the coroutine
co = nil
end
end

The line that faults, 1178, is copied here:

Code: [Select]

if(rc < 0) then --Something happened in the Gcode and we have an error So Kill the coroutine
The error message ':attempt to compare nil with numberstack ' tells me that it looks like the variable rc is nil, ergo comparing
a nil with a number results in an error. Reading the few lines previous to find the current vale of rc:

Code: [Select]

coerrorcheck, rc, m_CheckProbe = coroutine.resume(co)
if(coerrorcheck == false) then --Something happened here to the coroutine so kill it
co = nil
end
if(rc < 0) then --Something happened in the Gcode and we have an error So Kill the coroutine
Thus rc is assigned a value when this expression is evaluated:

Code: [Select]

coerrorcheck, rc, m_CheckProbe = coroutine.resume(co)
What I would like to suggest is to put a wxMessageBox diagnostic report statement immediately after the faulty expression
to establish if the assignment of rc is indeed of type nil.

I would therefore edit the mcTouchOff.lua file with this statement:

Code: [Select]

wx.wxMessageBox(" rc="..tostring(rc)) immediately after line 1178.

Run the code and see if the wxMessageBox indicates the value of rc, whether it be nil or otherwise.

This would not solve the problem but it would give you a way of digging in to find out why.

Craig

3227

Mach4 General Discussion / Poor Mans Wizard

« on: January 19, 2019, 01:29:30 PM »

Hi All,
as I promised I thought I would start a new thread to show an idea that I have used on a few occasions to generate
Gcode files.

This thread started with:

https://www.machsupport.com/forum/index.php?topic=39284.0

Where I wrote some code for OP to 'jewel' some material. Chad was interested in the idea of opening a file and putting
the Gcode in it rather than executing it immediately with successive mcCntlGcodeExecuteWait() API commands.

Here it is:

Code: [Select]

function m125()
local inst=mc.mcGetInstance()
-- create the wxFrame window
    mainframe = wx.wxFrame( wx.NULL,          -- no parent
                        wx.wxID_ANY,          -- whatever for wxWindow ID
                        "DummyFrame", -- frame caption
                        wx.wxDefaultPosition, -- place the frame in default position
                        wx.wxDefaultSize,     -- default frame size
                        wx.wxDEFAULT_FRAME_STYLE ) -- use default frame styles

    -- create a panel in the frame
    panel = wx.wxPanel(mainframe, wx.wxID_ANY)--We are not going to show it but we need to have this to use the File dialog

local file = wx.wxFileDialog(panel, "Select Data File", "", "", "Text files (*.txt)|*.txt|Tap files (*.tap)|*.tap",
                             wx.wxFD_SAVE,wx.wxDefaultPosition,wx.wxDefaultSize, "File Dialog" );
        if(file:ShowModal() == wx.wxID_OK)then
            path = file:GetPath()
            fileHandle=io.open(path,"w+")
        end
--
--
--
--
-- Jewel Data.....to be edited as required
--
local jewelWidth=50
local jewelLength=100
local toolDiameter=6
local nominalStepover=0.66
local plungeSpeed=300
local retractZ=2
local safeZ=20
local jewelDwellTime=500
--
-- End of data block
--
local startXpos
local startYpos
local jewelZheight

local stepoverX,numjewelX
local stepoverY,numjewelY
local i=0
local j=0
-- Save the current position as the start of the jeweling area....you have jogged to the start haven't you????
startXpos=mc.mcCntlGcodeInterpGetPos(inst,mc.X_AXIS)
startYpos=mc.mcCntlGcodeInterpGetPos(inst,mc.Y_AXIS)
jewelZheight=mc.mcCntlGcodeInterpGetPos(inst,mc.Z_AXIS)
-- Calculate the required step over to meet the nominal step over as closely as possible but be an integral
-- number of 'jewels'
-- Reduce jewelWidth in X and Y by the diameter of the tool
jewelWidth=jewelWidth-toolDiameter
jewelLength=jewelLength-toolDiameter
-- Calculate the exact number of 'jewels' required to match the nomininal Steppover
numjewelX=jewelWidth / (nominalStepover * toolDiameter)
numjewelY=jewelLength / (nominalStepover * toolDiameter)
-- Find the integer number of 'jewels'
numjewelX=math.modf(numjewelX)
numjewelY=math.modf(numjewelY)
-- Calculate the actual stepover to be used so that an integral number of 'jewels' are perfomed
stepoverX=jewelWidth / numjewelX
stepoverY=jewelLength / numjewelY
--
--
local retract="g0 z "..tostring(jewelZheight+retractZ)
local safeHeight="g0 z "..tostring(jewelZheight+safeZ)
--mc.mcCntlGcodeExecute(inst,retract..'\n'..'g1 f'..tostring(plungeSpeed)..'\n')
fileHandle:write(retract..'\n'..'g1 f '..tostring(plungeSpeed)..'\n')
for i=0,numjewelX,i+1 do
for j=0,numjewelY,j+1  do
jewelX=startXpos + (i * stepoverX)
jewelY=startYpos + (j * stepoverY)
--mc.mcCntlGcodeExecute(inst,'g0 x '..tostring(jewelX)..' y '.. tostring(jewelY)..'\n'..
-- 'g1 z '..tostring( jewelZheight)..'\n'..
-- 'g4 p'..tostring(jewelDwellTime)..'\n'..
-- retract..'\n')
fileHandle:write('g0 x '..tostring(jewelX)..' y '..tostring(jewelY)..'\n')
fileHandle:write('g1 z '..tostring(jewelZheight)..'\n')
fileHandle:write('g4 p '..tostring(jewelDwellTime)..'\n')
fileHandle:write(retract..'\n')
end
end
--mc.mcCntlGcodeExecuteWait(inst,safeHeight)
fileHandle:write(safeHeight..'\n')
fileHandle:flush()
fileHandle:close()
end
if (mc.mcInEditor()==1)then
m125()
end

Essentially all I have done is open a file dialogue so you can open a new file, or open an existing file with a normal Browse window
and then use exactly the same code that did the jeweling but replaced the mc.CntlGcodeExecuteWait() commands (I just
commented them out) with suitable file write commands.

Note that this code will run if you MDI <m125>.

The procedure would then be:
1) Jog to the location of the first (lower lefthand) 'jewel'
2) Lower the Z axis until the tool/brush makes contact with the material with sufficient force to effect the jewel
3) MDI <m125>

I have attached a coy of the file generated. Not very sophisticated....at best a poor mans Wizard.....and I am a poor man!

Craig

3228

Mach4 General Discussion / Re: Plasma table - Dry Run feature in M3 macro

« on: January 19, 2019, 12:46:01 PM »

Hi Jamie,
I'm not quite sure who all the personell at NFS are but Steve is one of the most active and prolific developers of Mach4.
Take a little time and read some of his posts, they are the clearest and most concise illuminations of how Mach works.

Steve has also commented in the past he hates writing documentation........hey, a guy can't be good at everything!
He is always leaping ahead with new ideas and developments.

Craig

3229

Mach4 General Discussion / Re: How to generate gcode to do pearling

« on: January 19, 2019, 12:34:34 PM »

Hi Chad,
the only real difficulty in opening existing files or creating new ones is using/having a file dialog which means wxLua.

In the LuaExamples folder are two macros m400() and m401() which are opening, creating and populating a probe file.
The file dialog code I use and have reused is just an edited version of that code.

Code: [Select]

-- create the wxFrame window
    mainframe = wx.wxFrame( wx.NULL,          -- no parent
                        wx.wxID_ANY,          -- whatever for wxWindow ID
                        "DummyFrame", -- frame caption
                        wx.wxDefaultPosition, -- place the frame in default position
                        wx.wxDefaultSize,     -- default frame size
                        wx.wxDEFAULT_FRAME_STYLE ) -- use default frame styles

    -- create a panel in the frame
    panel = wx.wxPanel(mainframe, wx.wxID_ANY)--We are not going to show it but we need to have this to use the File dialog

local file = wx.wxFileDialog(panel, "Select Data File", "", "", "Text files (*.txt)|*.txt|Tap files (*.tap)|*.tap",
                             wx.wxFD_SAVE,wx.wxDefaultPosition,wx.wxDefaultSize, "File Dialog" );
        if(file:ShowModal() == wx.wxID_OK)then
            path = file:GetPath()
            outfile=assert(io.open(tostring(path),'w+'))
        end
This is an example of that code. Note that the frame and panel are nothing special but they need to be present so the
file dialog can happen. This is the critical line:

local file = wx.wxFileDialog(panel, "Select Data .....................................................faultSize, "File Dialog" );

The remaining code is all about using functions of the data structure "file", for instance:

file:ShowModal() == wx.wxID_OK                                 and:

path = file:GetPath()

The line which opens the file is:

outfile=assert(io.open(tostring(path),'w+'))                    but that is inelegant, this is an example of a file opening statement
                                                                                   that I wrote for a job a week or so ago:

local fileHandle=io.open(pathfilename,"w+")                   and some of the statements for writing to, flushing and closing the
                                                                                   file using this syntax are:

fileHandle:write(offset,'\n')
fileHandle:flush()
fileHandle:close()

I'm sort of thinking that opening and closing files is getting a bit away from the subject of this thread and am likely to confuse
the hell out of OP if I start posting code in the same thread. I will start a new thread where I will write the generated Gcode
to a file, sort of a poor mans Wizard.

Craig.

3230

Mach4 General Discussion / Re: How to generate gcode to do pearling

« on: January 19, 2019, 06:43:02 AM »

Hi,
well pearling or jeweling ...I don't care. I notice near the end of the article it shows the overlap pattern.
I did not consider such a pattern when I wrote the code I've posted. Such a pattern should not be hard
to code.

In fact as you can see there is nothing particularly difficult abut the code I have posted.
Lua itself is reasonably simple, but don't let its simplicity fool you, there are a number of features/ideas,
'functions as first class values, for instance that mean Lua can be used to achieve a very wide range of
programming paradigms despite its simplicity.

A major part in successfully coding in Lua for Mach4 is to know and understand the API. Its made a little more difficult
because the development of features in Mach4 have exceeded the documentation. I know its frustrating but it seems we can
have newly developed features OR up-to-date documentation....but apparently not both. Not withstanding my frustration
with documentation I am delighted with the breadth and scope of newly developed features.

Smurph has indicated that Surface Mapping is close as is THC support functions which should allow much easier implementation
of THC into motion control boards.

Anyway, happy coding.

Craig